1. Field of the Invention
The present invention relates to a titanium oxide composite, a titanium oxide composite manufacturing method, and a super capacitor using the same. More particularly, the present invention relates to a titanium oxide composite in which an electronic conductivity is enhanced by forming graphene on a surface of granular titanium oxide, a titanium oxide composite manufacturing method, and a hybrid super capacitor using the same.
2. Description of the Related Art
A super capacitor is used for a large capacity energy storage device and technology for electrode materials is under development in order to increase a density of energy to be stored. In view of the battery performance of the super capacitor, a cathode material may play an important role. Lithium-titanium oxide (LTO) has a structurally stable spinel structure as a cathode active material.
Due to a “zero-strain” characteristic that a volume expansion barely occurs in charging and discharging, LTO may have an advantage such as a high cyclic characteristic. Accordingly, LTO has been currently used as a cathode material having a high output and a long lifespan, for example, an electrode material of an ultra high capacity super capacitor.
Korean Laid-Open Publication No. 2011-0013460 discloses a manufacturing method of LTO including mixing lithium carbonate powers or lithium hydroxide powders with titanium oxide by using the titanium oxide as a sintering precursor; using, as the sintering precursor, a titanium and lithium containing compound from a solution containing both titanium and lithium components; and manufacturing a mixture of titanium compound powders and lithium compound by manufacturing a mixture slurry of titanium compound powders and lithium-containing compound and then depositing the lithium compound through spray drying; and using the mixture as the sintering precursor.
The conventional LTO manufactured according to the disclosure of Korean Laid-Open Publication No. 2011-0013460 has a difficult in fast charging and discharging due to a low electronic conductivity. In addition, a theoretical capacity is about 175 mAh/g and thus, is low.